Nutritious food and public health risks: Insights on foodborne pathogens in edible land snails : A thesis submitted in partial fulfilment of the requirements for the Degree of Doctor of Philosophy at Lincoln University

The edible part of a snail is the ‘foot’ commonly termed snail meat. It contains high-quality protein, low fat, high calcium, magnesium, iron, and little or no cholesterol. Researchers believe that a continuous consumption of snail meat could support healthy immune systems, thus, preventing acute to severe health conditions such as obesity, type 2 diabetes, cardiovascular diseases, and certain cancers. People are becoming informed of these health benefits and their consumption of snail meat is gradually increasing especially in many communities in Africa and Europe. However, snail farming or heliciculture is still under-developed around the world. Snail-consuming populations have often picked land snails from locations that include, swamps, forests, gardens, footpaths, farmlands, household wastes, stones, and logs of wood or termed ‘anywhere’. The close association of land snails with the soil and decaying vegetation, coupled with its uncontrolled free-living and feeding patterns, could make them susceptible to microbial contamination. Consequently, humans could easily get exposed to foodborne pathogens in these ‘snail picking’ locations or during the handling and/or consumption of snail meat. The aim of this PhD thesis was to understand foodborne disease health risks in the handling and/or consumption of snail meat, which is currently a desirable source of food among rural communities in sub-Saharan Africa. Specifically, this research focused on land or terrestrial snails where I sought to 1) explore human foodborne pathogen exposures in snail handling and/or consumption practices, 2) determine the prevalence of potential foodborne pathogens (Shigatoxigenic E. coli (STEC), Campylobacter spp., Salmonella spp., Listeria spp., and Yersinia spp.) in edible land snails collected from different natural habitats (farms and within dwellings) and local markets, and 3) evaluate the survival characteristics of STEC and non-STEC strains in the faeces of edible land snails. To achieve these research objectives, a ...